This invention relates to a recording and reproducing device for recording data on an optical disk and reproducing data recorded on the optical disk, a recording optical disk device exclusively used for recording data on an optical disk, a reproducing device exclusively used for reproducing data recorded on the optical disk, and a replacement processing method for effecting replacement process for a defect area or defect areas in the optical disk device.
Conventionally, an optical disk device for recording data on an optical disk having recording tracks or reproducing data recorded on the optical disk uses laser light emitted from a semiconductor laser oscillator mounted on an optical head.
With the above optical disk device, data is recorded on the optical disk in units of one ECC block, each block being constructed by a plurality of sectors.
In this case, an optical disk device is proposed in which whether or not data is correctly recorded in units of one sector is determined at manufacturing time or at an initial time such as the application starting time, and if a sector with a defect is detected by the above determination process, the ECC block containing the defective sector is classified as a defective block and is treated as an unusable block.
Therefore, when successive data items such as speeches or moving pictures are recorded and if an ECC block (defective block) which is unusable is present, a slip replacement process for recording data on a next ECC block after skipping over the defective ECC block is effected. That is, the data recording operation is interrupted for a period of time corresponding to one ECC block.
Thus, the conventional optical disk device has a problem such that the reproducing operation is interrupted for a period of time corresponding to one defective ECC block, for example, when successive data items such as speeches or moving pictures are reproduced.
Further, the conventional device has a process for determining whether or not data has been correctly recorded for each sector at the recording time after the initial time, dealing with a defective sector as an unusable sector if the defective sector is detected by the above determining process and recording data by using a sector prepared in a different area for replacement.
In this case, if data recorded on the sector of the different area is not simultaneously reproduced when one ECC block is reproduced, reproduction of the whole ECC block cannot be effected. That is, originally, the sectors of one ECC block can be successively reproduced, but in this case, it becomes necessary to reproduce the sector for replacement in the course of reproduction of the ECC block and then successively reproduce the sectors of the original ECC block. Therefore, the reproduction speed is lowered.